Simple and Cheap ROBOT HAND Using Only ONE MOTOR!

Introduction: Simple and Cheap ROBOT HAND Using Only ONE MOTOR!

I just wanted to share this idea to make a simple, cheap robotic hand (or any end effector) using only one motor.

Using only ONE motor for the whole hand allows the hand to be:
- extremely cheap, which is good for your wallet because usually servomotor are quite expensive
- extremely light, which is good for your project because usually the main problem of an end effector is to be too much heavy, because the distance from the center of gravity of the robot multiplies its weight.

Of course, if you need to make a complex animatronic hand, capable of moving each finger individually, there's no choice, you will need a motor for every finger/ group of fingers you want to move separately.But, if you want to make a simple but effective end effector for your DIY robot, probably you should consider the idea of using just one motor for the whole hand!

In the video above you can see how the hand is made, and some test of the gripper.
I hope this can be useful to somebody!

FAQ (under construction):
The diameter of the hose is 1.5 cm.
The thickness of the hose is approximately 3mm for thumb, index, middle, and 2mm for ring and pinkie (if you see the video if can recognize two different kind of hoses). This is because a thicker hose is harder to pull, but is more effective to create the opposable thumb mechanism.

@DreamDragon: Thank you for your hint. Up to now, a rough calibration of the pressure of each finger can be done only adjusting the screws of the "Yoke". Furthermore, if you notice the hose of the thumb, index and middle finger is different from middle and pinkie: I used a thicker hose in order to achieve a better opposable thumb mechanism. I know that for any real application a quite accurate ( usually quite complicated) positioning is needed. Anyway, so far I was just focused on the gripper!

That's a really interesting piece of work. I love the Hose as armature, but it's really only a one motor gripper, and that's not really a new idea. Perhaps modifying the "Yoke" with a selection of rubber bands to give some variation in grip pressure on different fingers might be an interesting possibility,but the real key is the positioning. For accurate positioning you will need a lot more articulation.